Question 25
Fill in the blanks in at least 5 different ways with integers:
(a)
(b)
(c)
We need to find different sets of integers to make each equation true.
Step 1 — Understanding the first equation
The first equation is . Let us call the numbers in the blanks , , and . So, the equation is . Remember the order of operations: multiplication happens before addition. This means we first calculate , then add to that result. So, must equal -36.
Step 2 — Finding integers for (a) - Way 1
Let us choose values for and . We will choose as -6 and as 6. First, we multiply and .
Now, we need to find such that . To find , we add 36 to both sides.
So, the numbers are 0, -6, and 6. Let us check this in the original equation.
Step 3 — Finding integers for (a) - Way 2
Let us choose as -5 and as 8. First, we multiply and .
Now, we need to find such that . To find , we add 40 to both sides.
So, the numbers are 4, -5, and 8. Let us check this in the original equation.
Step 4 — Finding integers for (a) - Way 3
Let us choose as -8 and as 4. First, we multiply and .
Now, we need to find such that . To find , we add 32 to both sides.
So, the numbers are -4, -8, and 4. Let us check this in the original equation.
Step 5 — Finding integers for (a) - Way 4
Let us choose as -8 and as 6. First, we multiply and .
Now, we need to find such that . To find , we add 48 to both sides.
So, the numbers are 12, -8, and 6. Let us check this in the original equation.
Step 6 — Finding integers for (a) - Way 5
Let us choose as 3 and as -11. First, we multiply and .
Now, we need to find such that . To find , we add 33 to both sides.
So, the numbers are -3, 3, and -11. Let us check this in the original equation.
Step 7 — Understanding the second equation
The second equation is . Let us call the numbers in the blanks , , and . So, the equation is . Remember the order of operations: we first calculate inside the parenthesis . Then we multiply that result by . The product of and must be 12. This means must be a factor of 12.
Step 8 — Finding integers for (b) - Way 1
Let us choose a value for . We will choose as 1. Now, we need . This means must be 12. We need two numbers and whose difference is 12. Let us choose as 1. Then . To find , we add 1 to both sides.
So, the numbers are 13, 1, and 1. Let us check this in the original equation.
Step 9 — Finding integers for (b) - Way 2
Let us choose as 2. Now, we need . To find , we divide 12 by 2.
We need two numbers and whose difference is 6. Let us choose as 4. Then . To find , we add 4 to both sides.
So, the numbers are 10, 4, and 2. Let us check this in the original equation.
Step 10 — Finding integers for (b) - Way 3
Let us choose as -6. Now, we need . To find , we divide 12 by -6.
We need two numbers and whose difference is -2. Let us choose as 3. Then . To find , we add 3 to both sides.
So, the numbers are 1, 3, and -6. Let us check this in the original equation.
Step 11 — Finding integers for (b) - Way 4
Let us choose as 3. Now, we need . To find , we divide 12 by 3.
We need two numbers and whose difference is 4. Let us choose as 10. Then . To find , we add 10 to both sides.
So, the numbers are 14, 10, and 3. Let us check this in the original equation.
Step 12 — Finding integers for (b) - Way 5
Let us choose as 4. Now, we need . To find , we divide 12 by 4.
We need two numbers and whose difference is 3. Let us choose as 13. Then . To find , we add 13 to both sides.
So, the numbers are 16, 13, and 4. Let us check this in the original equation.
Step 13 — Understanding the third equation
The third equation is . Let us call the numbers in the blanks , , and . So, the equation is . Remember the order of operations: we always work from the innermost parenthesis first. First, we calculate . Then we subtract this result from . The final result must be -1.
Step 14 — Finding integers for (c) - Way 1
Let us choose values for and . We will choose as 10 and as 4. First, we calculate .
Now, we need to find such that . To find , we add 6 to both sides.
So, the numbers are 5, 10, and 4. Let us check this in the original equation.
Step 15 — Finding integers for (c) - Way 2
Let us choose as 3 and as 2. First, we calculate .
Now, we need to find such that . To find , we add 1 to both sides.
So, the numbers are 0, 3, and 2. Let us check this in the original equation.
Step 16 — Finding integers for (c) - Way 3
Let us choose as 1 and as 1. First, we calculate .
Now, we need to find such that . This means must be -1.
So, the numbers are -1, 1, and 1. Let us check this in the original equation.
Step 17 — Finding integers for (c) - Way 4
Let us choose as 0 and as 4. First, we calculate .
Now, we need to find such that . Remember that subtracting a negative number is the same as adding a positive number. So, . To find , we subtract 4 from both sides.
So, the numbers are -5, 0, and 4. Let us check this in the original equation.
Step 18 — Finding integers for (c) - Way 5
Let us choose as -5 and as 4. First, we calculate .
Now, we need to find such that . Remember that subtracting a negative number is the same as adding a positive number. So, . To find , we subtract 9 from both sides.
So, the numbers are -10, -5, and 4. Let us check this in the original equation.
Answer
(a) [ ] + [ ] x [ ] = -36 (i) 0 + (-6) x 6 = -36 (ii) 4 + (-5) x 8 = -36 (iii) -4 + (-8) x 4 = -36 (iv) 12 + (-8) x 6 = -36 (v) -3 + 3 x (-11) = -36
(b) ([ ] - [ ]) x [ ] = 12 (i) (13 - 1) x 1 = 12 (ii) (10 - 4) x 2 = 12 (iii) (1 - 3) x (-6) = 12 (iv) (14 - 10) x 3 = 12 (v) (16 - 13) x 4 = 12
(c) ([ ] - ([ ] - [ ])) = -1 (i) (5 - (10 - 4)) = -1 (ii) (0 - (3 - 2)) = -1 (iii) (-1 - (1 - 1)) = -1 (iv) (-5 - (0 - 4)) = -1 (v) (-10 - (-5 - 4)) = -1
More questions in FIO
Let us try to find a few more pairs of numbers from their sums and differences:
(a) Sum = 27, Difference = 9
(b) Sum = 4, Difference = 12
(c) Sum = 0, Difference = 10
(d) Sum = 0, Difference = -10
(e) Sum = -7, Difference = -1
(f) Sum = -7, Difference = -13
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Fill in the blanks in at least 5 different ways with integers:
(a)
(b)
(c)